Yeah, Midrange Hunter typically loses to any decent aggro deck, but it's not unwinnable for them. The problem is that most (maybe all) of the known aggro decks do terrible against Zoo, the other popular deck on the ladder right now. Backspace Rogue probably does a little better now than it used to because post-Naxx Zoo is slower. I was trying out Aggro Warrior again and I found that I really have to faceroll to even stand a chance at beating Zoo. Their minions are better/stickier than mine so I can't really be bothered to trade unless absolutely necessary. It does do pretty well against Midrange Hunter, however. Maybe Aggro Hunter does OK vs. Zoo as well? I don't remember. I haven't played that deck in months.
I feel like I'm walking around lost in this new "meta" (read: lack thereof) right now and kind of struggling on ladder atm. Admittedly I haven't pushed nearly as hard as last season though. I'm also in a weird spot where I have enough dust to craft one of three decks that I was never able to play before. It's between a variant of Warrior Control, standard Paladin Midrange/Control and Freeze Mage without Giants. Freeze Mage actually excites me the most, but it seems extremely weak in the Naxx meta (Loatheb, Hunters are everywhere, Warrior Control is more popular etc). I think Freeze Mage would have to look completely different if it was to function now. Pally and Warrior play very similarly, so it's hard to pick even between these two if it came down to it. Ultimately I want something that could complement Midrange Hunter in a tournament setting where there are BO3s and BO5s, but at the same time I don't want a lineup that loses to a single deck/class.
As far as buying Naxx, I've been F2P the whole time and had just been grinding in general. When I heard the announcement of Naxx, I started hoarding gold almost immediately. I've got just enough for the final wing next week and then I'll be back at 0 or close to it.